History gives us a trace of their partnership; they have always worked together. This leads to claims of inappropriate supervision during the project on site. When two companies have been working together for a long time, the probability of taking risks increases and they become careless. Their story together was mostly successful; most of their work on other airports survived, so ADP had little need to worry about building ADPi. Their selfishness led to the downfall of the structure. Nothing is perfect, not even a design orchestrated by chief architect Andreu. ADPi may have gotten confused during the process and instead of asking questions, they continued with their work as usual, despite the risks involved. Two problems may have occurred; supervisors were misinformed about the design and conveyed the information incorrectly, or construction workers were misinformed and supervisors did not notice. In case supervisors were misinformed or confused by the design, they should have asked questions. They confidently dictated directions that might have been incorrect. Their confidence may have erased any confusion they felt before giving orders. Contractors should always have a complete understanding of the design and process; the chief architect and chief engineers should